This invention relates to certain diphenylbutylamines which have been found to be extremely useful for the treatment of cardiac arrhythmias.
Intense interest has recently developed in drugs which help to control heart arrhythmias due to the severity of heart diseases in general and to the various types of cardiac arrhythmias plaguing mankind. Several N-phenyl-N-indanyl alkylenediamines have recently been prepared and evaluated as antiarrhythmic agents, as described in Canadian Pat. No. 910907. Drugs such as quinidine, procainamide, and lidocaine, have experienced wide usage in the treatment of various arrhythmias, even though severe problems often accompany their usage. For example, toxic doses of quinidine can induce ventricular tachycardia. Procainamide sometimes causes fever, chills, headache, skin rashes, and similar allergic reactions. Like several other antiarrhythmic agents, continued quinidine and procainamide usage may actually precipitate adverse myocardial effects such as ventricular tachycardia and fibrillation.
Research scientists are actively engaged in finding improved antiarrhythmic agents. To this end, certain diphenylalkylamines have now been found to be extremely useful in the treatment of cardiac arrhythmias.
Numerous diphenylalkylamines have been prepared by various investigators and have been shown to be useful as analgesics, anesthetics, antihistamines, antispasmodics, and the like. Janssen, for example, prepared and studied several diphenylpropylamines as analgesics, as described in detail in Synthetic Analgesics Part 1, Diphenylpropylamines, Pergamon Press, 1960. Adamson prepared several diphenylbutylamines and diphenylpropylamines and studied their antispasmodic and anesthetic activities, as described in British Pat. No. 624,117. Nowhere has it been taught that diphenylalkylamines might be useful as antiarrhythmic agents. I have now discovered that certain diphenylbutylamines are especially suited to treating cardiac arrhythmias.
An object of this invention is to provide certain compounds useful for the therapeutic and prophylactic treatment of heart arrhythmias.